296c6cfb66574bed0c71114b0953f6c16350f4d4
[strongswan.git] / Source / charon / payloads / nonce_payload.c
1 /**
2 * @file nonce_payload.h
3 *
4 * @brief Declaration of the class nonce_payload_t.
5 *
6 * An object of this type represents an IKEv2 Nonce-Payload.
7 *
8 */
9
10 /*
11 * Copyright (C) 2005 Jan Hutter, Martin Willi
12 * Hochschule fuer Technik Rapperswil
13 *
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU General Public License as published by the
16 * Free Software Foundation; either version 2 of the License, or (at your
17 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
18 *
19 * This program is distributed in the hope that it will be useful, but
20 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
21 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 * for more details.
23 */
24
25 /* offsetof macro */
26 #include <stddef.h>
27
28 #include "nonce_payload.h"
29
30 #include "encodings.h"
31 #include "../utils/allocator.h"
32
33
34
35 /**
36 * Private data of an nonce_payload_t' Object
37 *
38 */
39 typedef struct private_nonce_payload_s private_nonce_payload_t;
40
41 struct private_nonce_payload_s {
42 /**
43 * public nonce_payload_t interface
44 */
45 nonce_payload_t public;
46
47 /**
48 * next payload type
49 */
50 u_int8_t next_payload;
51
52 /**
53 * Critical flag
54 */
55 bool critical;
56
57 /**
58 * Length of this payload
59 */
60 u_int16_t payload_length;
61
62 /**
63 * the contained nonce value
64 */
65 chunk_t nonce;
66
67 /**
68 * @brief Computes the length of this payload.
69 *
70 * @param this calling private_nonce_payload_t object
71 * @return
72 * SUCCESS in any case
73 */
74 status_t (*compute_length) (private_nonce_payload_t *this);
75 };
76
77 /**
78 * Encoding rules to parse or generate a nonce payload
79 *
80 * The defined offsets are the positions in a object of type
81 * private_nonce_payload_t.
82 *
83 */
84 encoding_rule_t nonce_payload_encodings[] = {
85 /* 1 Byte next payload type, stored in the field next_payload */
86 { U_INT_8, offsetof(private_nonce_payload_t, next_payload) },
87 /* the critical bit */
88 { FLAG, offsetof(private_nonce_payload_t, critical) },
89 /* 7 Bit reserved bits, nowhere stored */
90 { RESERVED_BIT, 0 },
91 { RESERVED_BIT, 0 },
92 { RESERVED_BIT, 0 },
93 { RESERVED_BIT, 0 },
94 { RESERVED_BIT, 0 },
95 { RESERVED_BIT, 0 },
96 { RESERVED_BIT, 0 },
97 /* Length of the whole nonce payload*/
98 { PAYLOAD_LENGTH, offsetof(private_nonce_payload_t, payload_length) },
99 /* some nonce bytes, lenth is defined in PAYLOAD_LENGTH */
100 { NONCE_DATA, offsetof(private_nonce_payload_t, nonce) }
101 };
102
103 /**
104 * Implements payload_t's and nonce_payload_t's destroy function.
105 * See #payload_s.destroy or nonce_payload_s.destroy for description.
106 */
107 static status_t destroy(private_nonce_payload_t *this)
108 {
109 if (this->nonce.ptr != NULL)
110 {
111 allocator_free(this->nonce.ptr);
112 }
113 allocator_free(this);
114
115 return SUCCESS;
116 }
117
118 /**
119 * Implements nonce_payload_t's set_nonce function.
120 * See #nonce_payload_t.set_nonce for description.
121 */
122 static status_t set_nonce(private_nonce_payload_t *this, chunk_t nonce)
123 {
124 if (nonce.len >= 16 && nonce.len <= 256)
125 {
126 this->nonce.len = nonce.len;
127 this->nonce.ptr = nonce.ptr;
128 this->payload_length = NONCE_PAYLOAD_HEADER_LENGTH + nonce.len;
129 return SUCCESS;
130 }
131 return INVALID_ARG;
132 }
133
134 /**
135 * Implements nonce_payload_t's get_nonce function.
136 * See #nonce_payload_t.get_nonce for description.
137 */
138 static status_t get_nonce(private_nonce_payload_t *this, chunk_t *nonce)
139 {
140 nonce->len = this->nonce.len;
141 nonce->ptr = this->nonce.ptr;
142 return SUCCESS;
143 }
144
145 /**
146 * Implements payload_t's get_encoding_rules function.
147 * See #payload_s.get_encoding_rules for description.
148 */
149 static status_t get_encoding_rules(private_nonce_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
150 {
151 *rules = nonce_payload_encodings;
152 *rule_count = sizeof(nonce_payload_encodings) / sizeof(encoding_rule_t);
153
154 return SUCCESS;
155 }
156
157 /**
158 * Implements payload_t's get_type function.
159 * See #payload_s.get_type for description.
160 */
161 static payload_type_t get_type(private_nonce_payload_t *this)
162 {
163 return NONCE;
164 }
165
166 /**
167 * Implements payload_t's get_next_type function.
168 * See #payload_s.get_next_type for description.
169 */
170 static payload_type_t get_next_type(private_nonce_payload_t *this)
171 {
172 return (this->next_payload);
173 }
174
175 /**
176 * Implements payload_t's set_next_type function.
177 * See #payload_s.set_next_type for description.
178 */
179 static status_t set_next_type(private_nonce_payload_t *this,payload_type_t type)
180 {
181 this->next_payload = type;
182 return SUCCESS;
183 }
184
185 /**
186 * Implements payload_t's get_length function.
187 * See #payload_s.get_length for description.
188 */
189 static size_t get_length(private_nonce_payload_t *this)
190 {
191 this->compute_length(this);
192 return this->payload_length;
193 }
194
195 /*
196 * Described in header
197 */
198 nonce_payload_t *nonce_payload_create()
199 {
200 private_nonce_payload_t *this = allocator_alloc_thing(private_nonce_payload_t);
201 if (this == NULL)
202 {
203 return NULL;
204 }
205
206 this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
207 this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
208 this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
209 this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
210 this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
211 this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
212 this->public.destroy = (status_t (*) (nonce_payload_t *)) destroy;
213 this->public.set_nonce = (status_t (*) (nonce_payload_t *,chunk_t)) set_nonce;
214 this->public.get_nonce = (status_t (*) (nonce_payload_t *,chunk_t*)) get_nonce;
215
216 this->critical = FALSE;
217 this->next_payload = NO_PAYLOAD;
218 this->payload_length = NONCE_PAYLOAD_HEADER_LENGTH;
219 this->nonce.ptr = NULL;
220 this->nonce.len = 0;
221
222 return (&(this->public));
223 }
224
225